#include 
#include 
#include 
using namespace std;
typedef long long ll;
int n;
int h[100005];
int dp[100005];
int frog(int i) {
    if(i == n - 1) {
        return 0;
    }
    if(dp[i] != -1) {
        return dp[i];
    }
    int result = 2e9;
    if(i + 1 < n) {
        result = min(result, frog(i + 1) + abs(h[i] - h[i + 1]));
    }
    if(i + 2 < n) {
        result = min(result, frog(i + 2) + abs(h[i] - h[i + 2]));
    }
    dp[i] = result;
    return result;
}
int main()
{
    cin >> n;
    for(int i = 0; i < n; i++) {
        cin >> h[i];
        dp[i] = -1;
    }
    cout << frog(0) << endl;

    return 0;
}
// frog(0) --> (frog(1), frog(2))
// frog(1) --> frog(2), frog(3)